Circumference

Front

What is the formula to calculate the circumference of a circle?

Back

Circumference = 2 × π × radius or Circumference = π × diameter.

Front

If the radius of a circle is 10ft, what is the diameter?

Back

20ft.

Front

What is the relationship between diameter and radius?

Back

Diameter is twice the radius.

Front

If the diameter of a circle is 19 inches, what is the radius?

Back

9.5 inches.

Front

What does the term 'circumference' refer to?

Back

The distance around the circle.

Front

If a circle has a circumference of 31.4 cm, what is its radius?

Back

5 cm (using the formula C = 2πr).

Front

What is the circumference of a circle with a radius of 7 cm?

Back

43.96 cm (using the formula C = 2πr).

Front

What is the perimeter of a rectangle?

Back

Perimeter = 2 × (length + width).

Front

If a circle has a radius of 12 inches, what is its diameter?

Back

24 inches.

Front

What is the circumference of a circle with a diameter of 10 inches?

Back

31.4 inches (using the formula C = πd).